EN FOTOS: Preparativos del Mundial de Atletismo Beijing 2015

Andy Wong

Officials work on the track finishing line at the iconic Bird's Nest National Stadium as preparation for the upcoming 15th IAAF Athletics World Championships in Beijing Tuesday, Aug. 18, 2015. The 15th IAAF Athletics World Championships will be held in Beijing from Aug. 22 to 30. (AP Photo/Andy Wong) ORG XMIT: XAW103

Officials work on the track finishing line at the iconic Bird's Nest National Stadium as preparation for the upcoming 15th IAAF Athletics World Championships in Beijing Tuesday, Aug. 18, 2015. The 15th IAAF Athletics World Championships will be held in Beijing from Aug. 22 to 30. (AP Photo/Andy Wong) ORG XMIT: XAW103 (Andy Wong)

Officials work on the track finishing line at the iconic Bird's Nest National Stadium as preparation for the upcoming 15th IAAF Athletics World Championships in Beijing Tuesday, Aug. 18, 2015. The 15th IAAF Athletics World Championships will be held in Beijing from Aug. 22 to 30. (AP Photo/Andy Wong) ORG XMIT: XAW104

Officials work on the track finishing line at the iconic Bird's Nest National Stadium as preparation for the upcoming 15th IAAF Athletics World Championships in Beijing Tuesday, Aug. 18, 2015. The 15th IAAF Athletics World Championships will be held in Beijing from Aug. 22 to 30. (AP Photo/Andy Wong) ORG XMIT: XAW104 (Andy Wong)